Many basic powder compositions used for the preparation of both medicinal and thirst-quenching drinks are currently available commercially.
In general, carbonated drinks are prepared by dissolving CO2 under relatively high pressure in the liquid to be consumed. Maintaining the initial quantity of dissolved gas to which such drinks owe their "tingling" and thirst-quenching effect, necessitates the use of hermetically sealed containers which are capable of withstanding the internal pressure and are therefore relatively heavy and bulky, even for small quantities.
Effervescent mixtures in powder form are known which produce the same type of effect as that described above, with the exception that supersaturation of the liquid phase is virtually impossible under the conditions in which such drinks are usually prepared. It is impossible, using known mixtures, to prepare drinks in which CO2 is evolved at a constant rate throughout the entire period required for consumption. After the initial effervescence has occurred, a drink prepared in this way rapidly loses its character and becomes "flat" and even insipid. The invention permits the drawbacks associated with known effervescent mixtures to be overcome advantageously.